Air conditioning devices for cooling or heating an indoor space have been known. For example, an air conditioning device disclosed in Patent Document 1 includes an indoor unit mounted on a ceiling. The indoor unit includes an indoor fan and an indoor heat exchanger through which air carried by the indoor fan passes.
In an air conditioning device, the flow of a refrigerant in a refrigerant circuit is changed to perform a cooling operation or a heating operation selectively. In the heating operation, a refrigerant compressed by a compressor flows through an indoor heat exchanger of an indoor unit. In the indoor heat exchanger, the refrigerant dissipates heat into indoor air and then is condensed. The condensed refrigerant has its pressure reduced by the expansion valve, and is subsequently evaporated by an outdoor heat exchanger of an outdoor unit. The evaporated refrigerant is sucked into a compressor and compressed therein. In the cooling operation, a refrigerant compressed in the compressor flows through the outdoor heat exchanger of the outdoor unit. In the outdoor heat exchanger, the refrigerant dissipates heat to outdoor air and then is condensed. The condensed refrigerant has its pressure reduced by the expansion valve, and subsequently flows through the indoor heat exchanger of the indoor unit. In the indoor heat exchanger, the refrigerant absorbs heat from the indoor air, and then is evaporated. The evaporated refrigerant is then sucked into the compressor and is compressed therein.